RECENT EPA HOMELAND SECURITY RESEARCH WATER SECURITY PRODUCTS

From time to time, ASDWA receives very helpful updates from our colleagues at EPA’s National Homeland Security Research Center (NHSRC). And, as they have reminded us this time, “Many of our products have multiple uses, not just homeland security applications.” Please take a few moments to read through this impressive product list and consider how you can make the connections between these tools and products and other aspects of your drinking water program.

The original TEVA-SPOT software guided utilities in selecting the optimal number and location of water quality sensors to best meet their monitoring and security needs. The Consequence and Vulnerability Assessment Tool greatly improves this software by providing functions that enable utilities to make informed risk assessment and risk management decisions related to contamination events or operational upsets in water distribution systems (WDS). The tool can be used to prepare for events or to guide response as events are occurring.

Physiologically based pharmacokinetic (PBPK) modeling is a mathematical modeling technique for predicting the absorption, distribution, metabolism and excretion of synthetic or natural chemical substances in humans and other animal species. PBPK modeling is used in pharmaceutical research and drug development, and in health risk assessment. This second generation computational and informatics tools can be used to automatically organize and give rapid access to the body of PBPK modeling literature.

I-WASTE was developed to address waste management information gaps. I-WASTE provides information on types and volumes of waste materials and potential contaminants generated during an incident, location and contact information for potential treatment/disposal facilities, as well as health and safety information to ensure public and worker safety during the removal, transport, treatment, and disposal of contaminated waste and debris. The online tutorial was developed to assist EPA’s On Scene Coordinators and others in the use of the tool.

This book chapter discusses the general principles and characteristics of water and wastewater system security. The chapter also summarizes current research as it relates to system security, focusing on intentional threats to water systems.

CANARY is an EPA-developed software that enhances the detection of contamination incidents in drinking water distribution systems. One of the challenges to more widespread use of the software is the configuration process. This report presents a set of rule-of-thumb configuration parameters that can be used by water utilities as they start to use the software. In addition, a logical process is laid out for a more comprehensive approach to selecting configuration parameters.

CANARY event detection software was used for the purposes of detecting and identifying system response to rainfall in a permeable pavement stormwater underdrain in an academic parking lot in Cincinnati, OH. The results show that the software, originally designed for water quality detection in drinking water systems, proved adept at identifying a change in both underdrain flow and subsurface moisture in response to precipitation.

The purpose of this report is to provide EPA testing results of an on line radiation monitor for drinking water called the Beta Ram (B- Ram) by LabLogic Inc. Previous water monitoring systems have not been able to detect radiation at or near Protective Action Guides based upon 500 mrem/yr. This device using a scintillation principle of detection was able to detect at these lower activity levels. This information will help inform buyer decisions in the marketplace

The determination of the rodenticide tetramethylenedisulfotetramine (TETS) in drinking water is reportable through the use of automated sample preparation via solid phase extraction and detection using isotope dilution gas chromatography-mass spectrometry. The method was characterized over twenty-two analytical batches with quality control samples. Accuracies for low and high concentration quality control pools were 100 and 101%, respectively. The minimum reporting level (MRL) for TETS in this method is 0.50 ug/L. Five drinking waters, representing a range of water quality parameters and disinfection practices, were fortified with TETS at ten times the MRL and analyzed over a 28 day period to determine the stability of TETS in these waters. The amount of TETS measured in these samples averaged 100 ± 6% of the amount fortified suggesting that tap water samples may be held for up to 28 days prior to analysis.

PRODUCTS THAT SUPPORT THE TREATMENT OF WATER AND/OR DECONTAMINATION OF WATER INFRASTRUCTURE

This report summarizes the current state of knowledge on the persistence of chemical contamination on drinking water infrastructure along with information on decontamination should persistence occur. Decontamination options for drinking water infrastructure have been explored for some chemical contaminants, but important data gaps remain. In general, data on chemical persistence on drinking water infrastructure is available for inorganics such as arsenic and mercury, as well as select organics such as petroleum products, pesticides and rodenticides. Data specific to chemical warfare agents and pharmaceuticals was not found and data on toxins is scant. Future research suggestions focus on expanding the available chemical persistence data to other common drinking water infrastructure materials. Decontaminating agents that successfully removed persistent contamination from one infrastructure material should be used in further studies.

This article summarizes the current state of knowledge on the persistence of biological agents on drinking water infrastructure along with information on decontamination should persistence occur. Decontamination options for drinking water infrastructure have been explored for some biological agents, but data gaps remain. Data on bacterial spore persistence on common water infrastructure materials such as iron and cement-mortar lined iron shows that spores can be persistent for weeks after initial contamination. Decontamination data shows that common disinfectants such as free chlorine have limited effectiveness. Decontamination results with germinant and alternate disinfectants such as chlorine dioxide are more promising. Persistence and decontamination data was collected on vegetative bacteria, such as coliforms, Legionella and Salmonella. Vegetative bacteria are less persistent than spores and more susceptible to disinfection, but the surfaces and water quality conditions in many studies were only marginally related to drinking water systems. However, results of real-world case studies on accidental contamination of water systems with E. coli and Salmonella contamination show that flushing and chlorination can help return a water system to service. Some viral persistence data was found, but decontamination data was lacking. Future research suggestions focus on expanding the available biological persistence data to other common infrastructure materials. Further exploration of non-traditional drinking water disinfectants is recommended for future studies.

This article summarizes the current state of knowledge on the persistence of radiological agents on drinking water infrastructure along with information on decontamination should persistence occur. Decontamination options for drinking water infrastructure have been explored for some important radiological agents (cesium, strontium and cobalt), but important data gaps remain. Although some targeted experiments have been published on cesium, strontium and cobalt persistence on drinking water infrastructure, most of the data comes from nuclear clean-up sites. Furthermore, the studies focused on drinking water systems use non-radioactive surrogates. Non-radioactive cobalt was shown to be persistent on iron due to oxidation with free chlorine in drinking water and precipitation on the iron surface. Decontamination with acidification was an effective removal method. Strontium persistence on iron was transient in tap water, but adherence to cement-mortar has been demonstrated and should be further explored. Cesium persistence on iron water infrastructure was observed when flow was stagnant, but not with water flow present. Future research suggestions focus on expanding the available cesium, strontium and cobalt persistence data to other common infrastructure materials, specifically cement-mortar. Further exploration chelating agents and low pH treatment is recommended for future decontamination studies.